Method and apparatus for data transmission of terminal in wireless communication system

ABSTRACT

The present disclosure relates to a communication system and technique that may be applied to intelligent services based on a 5G communication technology and an IoT-related technology. The present disclosure provides a method for data transmission of a terminal in a wireless communication system that includes inputting a packet data convergence protocol packet data unit (PDCP PDU) output from a PDCP entity to a first radio link control (RLC) entity and a second RLC entity. The method also includes inputting a first radio link control packet data unit (RLC PDU) output from the first RLC entity and a second RLC PDU output from the second RLC entity to a medium access control (MAC) entity and transmitting a medium access control packet data unit (MAC PDU) output from the MAC entity through a first physical layer (PHY) entity and a second physical layer entity.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 17/099,520,filed Nov. 16, 2020, now U.S. Pat. No. 11,533,712, issued Dec. 20, 2022,which is a continuation of application Ser. No. 16/659,187, filed Oct.21, 2019, now abandoned, which is a continuation of application Ser. No.15/804,942, filed Nov. 6, 2017, now U.S. Pat. No. 10,455,551, issuedOct. 22, 2019, which is related to and claims priority to Korean PatentApplication No. 10-2016-0146654, filed Nov. 4, 2016, the disclosures ofwhich are herein incorporated by reference in their entirety.

BACKGROUND 1. Field

The present disclosure relates to a method for transmission andreception of data for ultra-reliable and low-latency communications(URLLC) in a wireless communication system.

2. Description of the Related Art

To meet a demand for radio data traffic that is on an increasing trendsince commercialization of a 4G communication system, efforts to developan improved 5G communication system or a pre-5G communication systemhave been conducted. For this reason, the 5G communication system or thepre-5G communication system is called a beyond 4G network communicationsystem or a post LTE system. To achieve a high data transmission rate,the 5G communication system is considered to be implemented in a veryhigh frequency (mmWave) band (e.g., like 60 GHz band). To relieve a pathloss of a radio wave and increase a transfer distance of the radio wavein the very high frequency band, in the 5G communication system,beamforming, massive MIMO, full dimensional MIMO (FD-MIMO), arrayantenna, analog beam-forming, and large scale antenna technologies havebeen discussed. Further, to improve a network of the system, in the 5Gcommunication system, technologies such as an evolved small cell, anadvanced small cell, a cloud radio access network (cloud RAN), anultra-dense network, a device to device communication (D2D), a wirelessbackhaul, a moving network, cooperative communication, coordinatedmulti-points (CoMP), and reception interference cancellation have beendeveloped. In addition to this, in the 5G system, hybrid FSK and QAMmodulation (FQAM) and sliding window superposition coding (SWSC) thatare an advanced coding modulation (ACM) scheme and a filter bank multicarrier (FBMC), a non orthogonal multiple access (NOMA), and a sparsecode multiple access (SCMA) that are an advanced access technology, andso on have been developed.

Meanwhile, the Internet is evolved from a human-centered connectionnetwork through which a human being generates and consumes informationto the Internet of Things (IoT) network that transmits/receivesinformation between distributed components such as things and processesthe information. The Internet of Everything (IoE) technology in whichthe big data processing technology, etc. is combined with the IoTtechnology by connection with a cloud server, etc. has also emerged. Toimplement the IoT, technology elements, such as a sensing technology,wired and wireless communication and network infrastructure, a serviceinterface technology, and a security technology, have been required.Recently, technologies such as a sensor network, machine to machine(M2M), and machine type communication (MTC) for connecting betweenthings have been researched. In the IoT environment, an intelligentInternet technology (IT) service that creates a new value in human lifeby collecting and analyzing data generated in the connected things maybe provided. The IoT may apply for fields, such as a smart home, a smartbuilding, a smart city, a smart car or a connected car, a smart grid,health care, smart appliances, and an advanced healthcare service, byfusing and combining the existing information technology (IT) withvarious industries.

Therefore, various tries to apply the 5G communication system to the IoTnetwork have been conducted. For example, the 5G communicationtechnologies, such as the sensor network, the machine to machine (M2M),and the machine type communication (MTC), have been implemented bytechniques such as the beamforming, the MIMO, and the array antenna. Theapplication of the cloud radio access network (cloud RAN) as the bigdata processing technology described above may also be considered as anexample of the fusing of the 5G communication technology with the IoTtechnology.

In accordance with recent development of long term evolution (LTE) andLTE-advanced (LTE-A), there is a need for a method and apparatus fortransmission and reception of data for ultra-reliable and low-latencycommunications (URLLC) in a wireless communication system.

SUMMARY

To address the above-discussed deficiencies, it is a primary object toprovide a method for transmission and reception of data forultra-reliable and low-latency communications (URLLC) in a wirelesscommunication system.

Another aspect of the present disclosure provides a method of using acorresponding resource if a terminal receives uplink resource allocationduring random access in a cell in which only a sounding reference signal(SRS) may be transmitted in uplink.

In accordance with an aspect of the present disclosure, a method fordata transmission of a terminal in a wireless communication system, themethod includes: inputting a packet data convergence protocol packetdata unit (PDCP PDU) output from a packet data convergence protocolentity to a first radio link control (RLC) entity and a second radiolink control entity, inputting a first radio link control packet dataunit (RLC PDU) output from the first radio link control entity and asecond radio link control packet data unit output from the second radiolink control entity to a medium access control (MAC) entity, andtransmitting a medium access control packet data unit (MAC PDU) outputfrom the medium access control entity through a first physical layerentity and a second physical layer entity.

The method may further include: receiving configuration information forduplicate input of the packet data convergence protocol packet data unitfrom a base station, in which the medium access control packet data unitis transmitted through the first physical layer entity and the secondphysical layer entity determined based on the configuration information.

Packet data convergence protocol packet data units input to the firstradio link control entity and the second radio link control entity,respectively, may have the same sequence number.

The first radio link control packet data unit and the second radio linkcontrol packet data unit may have different sequence numbers.

The first radio link control entity and the second radio link controlentity may be entities operated in an unacknowledged mode (UM) in whichretransmission through automatic repeat request (ARQ) is not performed.

The first physical layer entity and the second physical layer entity mayhave different frequencies for transmitting the medium access controlpacket data unit or different antennas for transmitting the mediumaccess control packet data unit in the same frequency.

In accordance with another aspect of the present disclosure, a methodfor data reception of a base station in a wireless communication system,the method includes: transmitting configuration information forduplicate generation of packet data convergence protocol packet dataunits to a terminal; and receiving the duplicately generated packet dataconvergence protocol packet data units based on the configurationinformation through a physical layer entity of the terminalcorresponding to each packet data convergence protocol packet data unit.

The duplicately generated packet data convergence protocol packet dataunits may have the same sequence number.

In accordance with another aspect of the present disclosure, a terminalin a wireless communication system includes: a transceiver configured totransmit and receive a signal; and a controller configured to controlthe transceiver to input a packet data convergence protocol packet dataunit output from a packet data convergence protocol entity to a firstradio link control entity and a second radio link control entity, inputa first radio link control packet data unit output from the first radiolink control entity and a second radio link control packet data unitoutput from the second radio link control entity to a medium accesscontrol entity, and transmit a medium access control packet data unitoutput from the medium access control entity through a first physicallayer entity and a second physical layer entity.

The controller may control the transceiver to receive configurationinformation for duplicate input of the packet data convergence protocolpacket data unit from a base station, and transmit the medium accesscontrol packet data unit through the first physical layer entity and thesecond physical layer entity based on the configuration information.

Packet data convergence protocol packet data units input to the firstradio link control entity and the second radio link control entity,respectively, may have the same sequence number.

The first radio link control packet data unit and the second radio linkcontrol packet data unit may have different sequence numbers.

The first radio link control entity and the second radio link controlentity may be entities operated in an unacknowledged mode (UM) in whichretransmission through automatic repeat request (ARQ) is not performed.

The first physical layer entity and the second physical layer entity mayhave different frequencies for transmitting the medium access controlpacket data unit or different antennas for transmitting the mediumaccess control packet data unit in the same frequency.

In accordance with another aspect of the present disclosure, a basestation in a wireless communication system includes: a transceiverconfigured to transmit and receive a signal; and a controller configuredto control the transceiver to transmit configuration information forduplicate generation of packet data convergence protocol packet dataunits to a terminal, and receive the duplicately generated packet dataconvergence protocol packet data units based on the configurationinformation through a physical layer entity of the terminalcorresponding to each packet data convergence protocol packet data unit.

In accordance with another aspect of the present disclosure, a methodfor uplink reference signal transmission of a terminal includesreceiving a first message for activating a cell in which only a soundingreference signal (SRS) may be transmitted in uplink, transmitting apreamble to the activated cell, receiving a second message includinguplink transmission resource information based on the preamble from thebase station, and determining whether to transmit the SRS based on theuplink transmission resource information.

According to an embodiment of the present disclosure, it is possible toincrease a reception success rate and, at the same time, decreaselatency when transmitting data.

According to another embodiment of the present disclosure, if a terminalreceives uplink resource allocation during random access in a cell inwhich only an SRS may be transmitted in uplink, it is possible toprevent unnecessary power consumption of the terminal or use thecorresponding resources by using the method proposed in the presentdisclosure.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document: the terms “include” and “comprise,” aswell as derivatives thereof, mean inclusion without limitation; the term“or,” is inclusive, meaning and/or; the phrases “associated with” and“associated therewith,” as well as derivatives thereof, may mean toinclude, be included within, interconnect with, contain, be containedwithin, connect to or with, couple to or with, be communicable with,cooperate with, interleave, juxtapose, be proximate to, be bound to orwith, have, have a property of, or the like; and the term “controller”means any device, system or part thereof that controls at least oneoperation, such a device may be implemented in hardware, firmware orsoftware, or some combination of at least two of the same. It should benoted that the functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely.Definitions for certain words and phrases are provided throughout thispatent document, those of ordinary skill in the art should understandthat in many, if not most instances, such definitions apply to prior, aswell as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIG. 1A illustrates a structure of an LTE system that is referred to fordescription of the present disclosure;

FIG. 1B illustrates a wireless protocol structure of an LTE system thatis referred to for description of the present disclosure;

FIGS. 1CA to 1CD illustrate a protocol structure of a transmission endand a reception end for ultra-reliable and low-latency communications(URLLC) for a predetermined traffic type/radio bearer according to anembodiment of the present disclosure;

FIG. 1D illustrates an operation of a terminal according to anembodiment of the present disclosure;

FIG. 1E illustrates a configuration of a terminal according to anembodiment of the present disclosure;

FIG. 1F illustrates a configuration of a base station according to anembodiment of the present disclosure;

FIG. 2A illustrates an example of a network structure of a wirelesscommunication system according to an embodiment of the presentdisclosure;

FIG. 2B illustrates a wireless protocol structure of the LTE system towhich the present disclosure is applied;

FIG. 2C illustrates carrier aggregation in a terminal;

FIG. 2D illustrates a frame structure of an LTE TDD system;

FIG. 2E illustrates message flow of a terminal and a base stationaccording to an embodiment of the present disclosure;

FIG. 2F illustrates an operation of a terminal according to anembodiment of the present disclosure; and

FIG. 2G illustrates a configuration of a terminal in a wirelesscommunication system according to an embodiment of the presentdisclosure.

DETAILED DESCRIPTION

FIGS. 1A through 2G, discussed below, and the various embodiments usedto describe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged electronic device.

Hereinafter, embodiments of the present invention will be described indetail with reference to the accompanying drawings. When it is decidedthat a detailed description for the known function or configurationrelated to the present disclosure may obscure the gist of the presentdisclosure, the detailed description therefor will be omitted. Further,the following terminologies are defined in consideration of thefunctions in the present disclosure and may be construed in differentways by the intention or practice of users and operators. Therefore, thedefinitions thereof should be construed based on the contents throughoutthe specification.

Various advantages and features of the present disclosure and methodsaccomplishing the same will become apparent from the following detaileddescription of embodiments with reference to the accompanying drawings.However, the present disclosure is not limited to the embodimentsdisclosed herein but will be implemented in various forms. Theembodiments have made disclosure of the present disclosure complete andare provided so that those skilled in the art can easily understand thescope of the present disclosure. Therefore, the present disclosure willbe defined by the scope of the appended claims. Like reference numeralsthroughout the description denote like elements.

Terms identifying an access node, terms indicating network entity, termsindicating messages, terms indicating an interface between networkentities, terms indicating various types of identification information,and so on that are used in the following description are exemplified forconvenience of explanation. Accordingly, the present disclosure is notlimited to terms to be described below and other terms indicatingobjects having the equivalent technical meaning may be used.

Hereinafter, for convenience of explanation, in the present disclosure,terms and names defined in a 3rd generation partnership project longterm evolution (3GPP LTE) standard which is the latest standard amongcommunication standards that currently exist are used. However, thepresent disclosure is not limited by the terms and names, and may beidentically applied to systems according to different standards. Inparticular, the present disclosure may be applied to a 3GPP new radio(NR, 5th generation mobile communication standard).

First Embodiment

The first embodiment proposes a method for transmission and reception ofdata for ultra-reliable and low-latency communications (URLLC) in awireless communication system.

FIG. 1A illustrates a structure of an LTE system that is referred to fordescription of the present disclosure.

Referring to FIG. 1A, the wireless communication system is configured ofa plurality of base stations 1 a-05, 1 a-10, 1 a-15, and 1 a-20, amobility management entity (MME) 1 a-25, and a serving-gateway (S-GW) 1a-30. A user equipment (hereinafter, UE or terminal) 1 a-35 accesses anexternal network through the base stations (evolved Node B (eNB)) 1a-05, 1 a-10, 1 a-15, and 1 a-20 and the S-GW 1 a-30.

The base stations 1 a-05, 1 a-10, 1 a-15, and 1 a-20 as access nodes ofa cellular network provide radio access to terminals accessing thenetwork. That is, the base stations 1 a-05, 1 a-10, 1 a-15, and 1 a-20performs scheduling by collecting state information such as bufferconditions of the terminals, a power headroom state, a channel state,and the like to provide traffic to users, thereby supporting connectionbetween the terminals and a core network (CN).

The MME 1 a-25 which is an apparatus performing various controlfunctions in addition to a mobility management function for a terminalis connected to a plurality of base stations, and the S-GW 1 a-30 is anapparatus providing a data bearer. Further, the MME 1 a-25 and the S-GW1 a-30 may further perform authentication for a terminal accessing thenetwork, bearer management, or the like, and process a packet arrivedfrom the base stations 1 a-05, 1 a-10, 1 a-15, and 1 a-20 or a packet tobe transferred to the base stations 1 a-05, 1 a-10, 1 a-15, and 1 a-20.

FIG. 1B illustrates a wireless protocol structure of an LTE system thatis referred to for description of the present disclosure.

Referring to FIG. 1B, a wireless protocol of the LTE system isconfigured of a packet data convergence protocol (PDCP) 1 b-05 and 1b-40, a radio link control (RLC) 1 b-10 and 1 b-35, and a medium accesscontrol (MAC) 1 b-15 and 1 b-30 in the terminal and the base station(eNB), respectively.

The PDCP 1 b-05 and 1 b-40 is responsible for an operation such as IPheader compression/decompression, and the like, and the radio linkcontrol (hereinafter, referred to as RLC) 1 b-10 and 1 b-35 reconfiguresa PDCP packet data unit (PDU) in an appropriate size.

The MAC 1 b-15 and 1 b-30 is connected to multiple RLC layer devicesconfigured in one terminal, and performs an operation of multiplexingRLC PDUs into an MAC PDU and demultiplexing RLC PDUs from an MAC PDU.

A physical layer (PHY) 1 b-20 and 1 b-25 performs an operation ofchannel-coding and modulating higher layer data and transmitting thehigher layer data in a form of an OFDM symbol through a radio channel,or demodulating and channel-decoding an OFDM symbol received through theradio channel and performing channel decoding for transmission to thehigher layer.

Further, the physical layer also uses a hybrid automatic repeat request(HARQ) for additional error correction, and a reception end transmits 1bit information indicating acknowledgement/negative-acknowledgement forreception of a packet transmitted from a transmission end. This isreferred to as HARQ ACK/NACK information.

Downlink HARQ ACK/NACK information for uplink transmission istransmitted through a physical hybrid-ARQ indicator channel (PHICH) anduplink HARQ ACK/NACK information for downlink transmission may betransmitted through a physical uplink control channel (PUCCH) or aphysical uplink shared channel (PUSCH).

A method for transmitting the HARQ may include asynchronous HARQ and asynchronous HARQ. The asynchronous HARQ is a method in which a timing atwhich retransmission for failed (re)transmission is performed is notfixed, and the synchronous HARQ is a method in which a timing at whichretransmission for failed (re)transmission is performed is fixed (e.g.,8 ms). Further, a plurality of transmission and reception may besimultaneously performed in parallel for uplink and downlink of oneterminal, and each transmission is classified by an HARQ processidentifier.

Meanwhile, in the asynchronous HARQ, since a retransmission timing isnot fixed, the base station provides information on to which HARQprocess the present transmission belongs, and information on whether thepresent transmission is initial transmission or retransmission to theterminal through a physical downlink control channel (PDCCH).

More specifically, the information on to which HARQ process the presenttransmission belongs is transmitted to the terminal through an HARQprocess ID field in the PDCCH, and the information on whether thepresent transmission is initial transmission or retransmission istransmitted through a new data indicator (NDI) bit in the PDCCH. If acorresponding bit is not changed from an existing value, it meansretransmission, and if the corresponding bit is changed to a differentvalue, it means new transmission.

Accordingly, the terminal receives resource allocation information inthe PDCCH transmitted by the base station to check details of thecorresponding transmission, thereby receiving actual data through aphysical downlink shared channel (PDSCH) in a case of downlink, andtransmitting actual data through a physical uplink shared channel(PUSCH) in a case of uplink.

Although not illustrated in FIG. 1B, a radio resource control(hereinafter, referred to as RRC) layer exists as a higher layer of thePDCP layers of the terminal and the base station, respectively, and theRRC layer may receive and transmit a configuration control messagerelated to access and measurement for radio resource control.

FIGS. 1CA to 1CD illustrate a protocol structure of a transmission endand a reception end for ultra-reliable and low-latency communications(URLLC) for a predetermined traffic type/radio bearer according to anembodiment of the present disclosure.

FIG. 1CA illustrates a method of generating a duplicate packet havingthe same sequence number (SN) in a PDCP layer 1 ca-01 for the samepacket of a predetermined traffic type/radio bearer and separatelytransmitting the generated duplicate packet through an independent RLClayer 1 ca-03 and 1 ca-05, MAC layer 1 ca-07 and 1 ca-09, and physicallayer 1 ca-11 and 1 ca-13. At this time, the PDCP layer performstransmission through different RLC layers and MAC layers for the samepacket.

Each physical layer 1 ca-15 and 1 ca-17 receiving the packets transmitsthe packets to MAC layers 1 ca-19 and 1 ca-21 corresponding thereto, thepackets are transmitted to RLCs 1 ca-23 and 1 ca-25, and finally, thepackets are transmitted to a PDCP layer 1 ca-27.

If respective packets transmitted through different paths all succeed intransmission and packets having the same SN arrive at the PDCP layer 1ca-27, the duplicate packet is discarded and only one packet istransmitted to a higher layer of the reception side.

The RLC layer may be assumed as an entity operated in an unacknowledgedmode (UM) in which retransmission through automatic repeat request (ARQ)for low latency communication is not performed. Further, the differentphysical layers may be spatially different resources using differentfrequencies, or using the same frequency and different antennas.

FIG. 1CB illustrates a method of generating a duplicate packet havingthe same SN in a PDCP layer 1 cb-01 for the same packet of apredetermined traffic type/radio bearer and transmitting the generatedduplicate packet through an independent RLC layer 1 cb-03 and 1 cb-05and a common MAC layer 1 cb-07. At this time, the PDCP layer performstransmission through different RLC layers for the same packet toseparately manage the SN in the RLC layer.

The MAC layer 1 cb-07 transmits the packets received from each RLClayers to the same physical layer or different physical layers 1 cb-11and 1 cb-13. Each physical layer 1 cb-15 and 1 cb-17 receiving thepackets transmits the packets to an MAC layer 1 ca-19 correspondingthereto, the packets are transmitted to RLCs 1 cb-23 and 1 cb-25, andfinally, the packets are transmitted to a PDCP layer 1 cb-27.

If respective packets transmitted through different paths all succeed intransmission and packets having the same SN arrive at the PDCP layer 1cb-27, the duplicate packet is discarded and only one packet istransmitted to a higher layer of the reception side.

Further, the RLC layer may be assumed as an entity operated in anunacknowledged mode (UM) in which retransmission through automaticrepeat request (ARQ) for low latency communication is not performed.Further, the different physical layers may be spatially differentresources using different frequencies, or using the same frequency anddifferent antennas.

FIG. 1CC illustrates a method in which the same PDCP, RLC layers areused for the same packet of a predetermined traffic type/radio bearer,but a duplicate packet is generated in an MAC layer, and the duplicatepacket is transmitted to the same physical layer or different physicallayers 1 cc-11 and 1 cc-13.

Each physical layer 1 cc-15 and 1 cc-17 receiving the packets transmitsthe packets to the corresponding MAC layer 1 cc-19, RLC layer 1 cc-23,and PDCP layer 1 cc-27. If the respective packets transmitted throughdifferent physical layers all succeed in transmission and the packetshaving a duplicate RLC SN arrive, the RLC layer 1 cc-23 discards theduplicate packet and transmits only one packet to the PDCP layer 1cc-27.

Further, the RLC layer may be assumed as an entity operated in anunacknowledged mode (UM) in which retransmission through automaticrepeat request (ARQ) for low latency communication is not performed.Further, the different physical layers may be spatially differentresources using different frequencies, or using the same frequency anddifferent antennas.

FIG. 1CD illustrates a method in which FIG. 1CA and FIG. 1CC arecombined. That is, a duplicate packet having the same sequence number(SN) in a PDCP layer 1 cd-01 for the same packet of a predeterminedtraffic type/radio bearer is generated and the generated duplicatepacket is transmitted through an independent RLC layer 1 cd-03 and 1cd-05, and MAC layer 1 cd-07 and 1 cd-09.

Each MAC layer 1 cd-07 and 1 cd-09 may generate a duplicate packet andtransmit the packets to physical layers 1 cd-11, 1 cd-12, 1 cd-13, and 1cd-14 corresponding to each MAC layer. Each physical layer 1 cc-15, 1cc-16, 1 cc-17, and 1 cc-18 receiving the packets transmits the receivedpackets to the corresponding MAC layers 1 cd-19 and 1 cd-21, and eachMAC layer transmits the packets to corresponding RLC layers 1 cd-23 and1 cd-25.

At this time, if all the packets successfully arrive at the RLC layers 1cd-23 and 1 cd-25 from the MAC layers 1 cd-07 and 1 cd-09, the duplicatepacket is discarded according to the RLC SN, and only one packet istransmitted to the corresponding PDCP layer 1 cd-27, and among thepackets received from each RLC layer, if all the packets successfullyarrive at the PDCP layer 1 cd-01, the duplicate packet is discardedaccording to the PDCP SN, and only one packet is transmitted to a higherlayer.

Further, the RLC layer may be assumed as an entity operated in anunacknowledged mode (UM) in which retransmission through automaticrepeat request (ARQ) for low latency communication is not performed.Further, the different physical layers may be spatially differentresources using different frequencies, or using the same frequency anddifferent antennas.

In the drawing, it is assumed that the terminal is already connected tothe base station and data transmission and reception are possible.

The terminal receives a message indicating configuration of duplicatetransmission for a predetermined traffic type/radio bearer from the basestation (1 d-03). The indicating message may include one of the number Mof duplicate packet generation in a PDCP layer and the number N ofduplicate packet generation in an MAC layer to be described below.

The M is the same as the number of a reception RLC device connected to aPDCP device configured for the radio bearer, thus the terminal mayadditionally generate an RLC layer as many as the number M. Further, theN may be a value specified by a resource allocation message orconfigured by the base station in the configuration message.

Next, when a packet corresponding to the traffic type and the radiobearer is generated in the terminal, if the number M of duplicate packetgeneration in a PDCP layer in the configuration message is 2 or more,the terminal generates duplicate packets as many as the number, andtransmits the duplicate packets to each RLC layer (1 d-05). At thistime, the PDCP layer of the terminal transmits the respective duplicatepackets to different RLC layers. Meanwhile, if the number N of duplicatepacket generation in each MAC layer in the configuration message is 2 ormore, the MAC layer receiving the packet from the RLC layer generates aduplicate packet for the corresponding packet (1 d-07). That is, thetotal number of duplicate packets is M*N, and a separate N value mayalso be set in each MAC layer.

The terminal transmits a resource request message to the base station totransmit the generated duplicate packet in uplink (that is, from theterminal to the base station) (1 d-09). The resource request message mayinclude at least one of an indicator indicating that a plurality ofduplicate packets are included and an identifier indicating that thepredetermined traffic type is included.

When receiving a resource allocation message for transmitting theduplicate packet from the base station receiving the resource requestmessage (1 d-11), the terminal transmits the duplicate packet to thebase station (1 d-13). At this time, the resource allocation message mayinclude at least one of information on a plurality of frequencies orspace resources described with reference to FIGS. 1CA to 1CD and anindicator indicating that it is allocation related to the ultra-reliableand low-latency traffic type.

By doing so, duplicate transmission of the same data to differentfrequencies or space resources may be made, thereby improvingreliability and decrease latency.

FIG. 1E illustrates a block configuration of a terminal in a wirelesscommunication system according to an embodiment of the presentdisclosure.

Referring to FIG. 1E, the terminal includes a radio frequency (RF)processor 1 e-10, a baseband processor 1 e-20, a storage unit 1 e-30,and a controller 1 e-40.

The RF processor 1 e-10 performs a function for transmitting andreceiving a signal through a radio channel such as band conversion,amplification, and the like of a signal. That is, the RF processor 1e-10 up-converts a baseband signal provided from the baseband processor1 e-20 into an RF band signal and transmits the up-converted signalthrough an antenna, and down-converts the PF band signal receivedthrough the antenna into the baseband signal.

For example, the RF processor 1 e-10 may include a transmission filter,a reception filter, an amplifier, a mixer, an oscillator, a digital toanalog converter (DAC), an analog to digital converter (ADC), and thelike. In FIG. 1E, only one antenna is illustrated, but the terminal mayinclude a plurality of antennas.

Further, the RF processor 1 e-10 may include a plurality of RF chains.Further, the RF processor 1 e-10 may perform beamforming. For thebeamforming, the RF processor 1 e-10 may adjust a phase and size of eachof signals transmitted and received through the plurality of antennas orantenna elements.

The baseband processor 1 e-20 performs a function of conversion betweena baseband signal and a bit string according to a physical layerstandard of the system. For example, at the time of data transmission,the baseband processor 1 e-20 generates complex symbols by encoding andmodulating a transmission bit string. Further, at the time of datareception, the baseband processor 1 e-20 restores a reception bit stringby demodulating and decoding the baseband signal provided from the RFprocessor 1 e-10.

For example, according to an orthogonal frequency division multiplexing(OFDM) scheme, at the time of data transmission, the baseband processor1 e-20 generates complex symbols by encoding and modulating atransmission bit string, maps the complex symbols, and then configuresOFDM symbols through inverse fast Fourier transform (IFFT) operation andcyclic prefix (CP) insertion. Further, at the time of data reception,the baseband processor 1 e-20 divides the baseband signal provided fromthe RF processor 1 e-10 into OFDM symbol units, restores signals mappedto subcarriers through fast Fourier transform (FFT) operation, and thenrestores a reception bit string through demodulation and decoding.

The baseband processor 1 e-20 and the RF processor 1 e-10 transmit andreceive a signal as described above. Accordingly, the baseband processor1 e-20 and the RF processor 1 e-10 may be referred to as a transmitter,a receiver, a transceiver, or a communication unit. Further, at leastone of the baseband processor 1 e-20 and the RF processor 1 e-10 mayinclude different communication modules to process signals of differentfrequency bands. The different frequency bands may include a super highfrequency (SHF) band (e.g., 2.5 GHz, 5 GHz), and a millimeter wave (mmwave) band (e.g., 60 GHz).

The storage unit 1 e-30 stores data such as a basic program foroperation of the terminal, an application program, configurationinformation, and the like.

The controller 1 e-40 controls overall operations of the terminal. Forexample, the controller 1 e-40 transmits and receives a signal throughthe baseband processor 1 e-20 and the RF processor 1 e-10. Further, thecontroller 1 e-40 records data in the storage unit 1 e-30 and reads thedata. To this end, the controller 1 e-40 may include at least oneprocessor.

For example, the controller 1 e-40 may include a communication processor(CP) performing a control for communication and an application processor(AP) controlling a higher layer such as an application program.According to an embodiment of the present disclosure, the controller 1e-40 includes a multi-connection processor 1 e-42 performing processingfor operation in a multi-connection mode. For example, the controller 1e-40 may control the terminal to perform the operation of the terminalillustrated in FIG. 1D.

The controller according to an embodiment of the present disclosuregenerates an RLC layer and an MAC layer for a predetermine beareraccording to a configuration received from the base station, andperforms duplicate transmission according to the set value at the timeof packet transmission of the corresponding bearer.

FIG. 1F illustrates a block configuration of a base station in awireless communication system according to an embodiment of the presentdisclosure.

As illustrated in FIG. 1F, a first access node is configured to includean RF processor 1 f-10, a baseband processor 1 f-20, a backhaulcommunication unit 1 f-30, a storage unit 1 f-40, and a controller 1f-50.

The RF processor 1 f-10 performs a function for transmitting andreceiving a signal through a radio channel such as band conversion,amplification, and the like of a signal. That is, the RF processor 1f-10 up-converts a baseband signal provided from the baseband processor1 f-20 into an RF band signal and transmits the up-converted signalthrough an antenna, and down-converts the PF band signal receivedthrough the antenna into the baseband signal.

For example, the RF processor 1 f-10 may include a transmission filter,a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC,and the like. In FIG. 1F, only one antenna is illustrated, but the firstaccess node may include a plurality of antennas. Further, the RFprocessor 1 f-10 may include a plurality of RF chains. Further, the RFprocessor 1 f-10 may perform beamforming. For the beamforming, the RFprocessor 1 f-10 may adjust a phase and size of each of signalstransmitted and received through the plurality of antennas or antennaelements.

The baseband processor 1 f-20 performs a function of conversion betweena baseband signal and a bit string according to a physical layerstandard of a first radio access technology. For example, at the time ofdata transmission, the baseband processor 1 f-20 generates complexsymbols by encoding and modulating a transmission bit string. Further,at the time of data reception, the baseband processor 1 f-20 restores areception bit string by demodulating and decoding the baseband signalprovided from the RF processor 1 f-10.

For example, according to the OFDM scheme, at the time of datatransmission, the baseband processor 1 f-20 generates complex symbols byencoding and modulating a transmission bit string, maps the complexsymbols, and then configures OFDM symbols through IFFT operation and CPinsertion. Further, at the time of data reception, the basebandprocessor 1 f-20 divides the baseband signal provided from the RFprocessor 1 f-10 into OFDM symbol units, restores signals mapped tosubcarriers through FFT operation, and then restores a reception bitstring through demodulation and decoding.

The baseband processor 1 f-20 and the RF processor 1 f-10 transmit andreceive a signal as described above. Accordingly, the baseband processor1 f-20 and the RF processor 1 f-10 may be referred to as a transmitter,a receiver, a transceiver, a communication unit, or a wirelesscommunication unit.

The backhaul communication unit 1 f-30 provides an interface forperforming communication with other nodes in the network. That is, thebackhaul communication unit 1 f-30 converts a bit string transmittedfrom the first access node to other node, for example, other accessnode, a core network, or the like, into a physical signal, and convertsthe physical signal received from the other node into a bit string.

The storage unit 1 f-40 stores data such as a basic program foroperation of the first access node, an application program,configuration information, and the like. In particular, the storage unit1 f-40 may store information on a bearer allocated to the accessedterminal, a measurement result reported from the accessed terminal, andthe like. Further, the storage unit 1 f-40 may provide information basedon which whether to provide multi-connection to the terminal or stop themulti-connection is determined. Further, the storage unit 1 f-40provides the stored data in response to a request of the controller 1f-50.

The controller 1 f-50 controls overall operations of the first accessnode. For example, the controller 1 f-50 transmits and receives a signalthrough the baseband processor 1 e-20 and the RF processor 1 e-10, orthe backhaul communication unit 1 f-30. Further, the controller 1 f-50records data in the storage unit 1 f-40 and reads the data. To this end,the controller 1 f-50 may include at least one processor.

According to an embodiment of the present disclosure, the controller 1f-50 indicates configurations for data transmission for URLLC to theterminal depending on capabilities of the terminal. Thereafter, whenreceiving a resource request from the terminal, a plurality of resourcesare allocated to different frequencies or space resources in responsethereto, and a packet is received from the terminal.

The methods according to the embodiments described in claims orspecification of the present disclosure may be implemented in a form ofhardware, software, or a combination of hardware and software.

In the case of implementation in the form of software, acomputer-readable storage medium that stores one or more programs(software module). The one or more programs stored in thecomputer-readable storage medium are configured for execution by one ormore processors in an electronic device. The one or more programsinclude instructions making the electronic device to execute the methodaccording to the embodiments described in claims or specification of thepresent disclosure.

The program (software module, software) may be stored in a random accessmemory, a non-volatile memory including a flash memory, a read onlymemory (ROM), an electrically erasable programmable read only memory(EEPROM), a magnetic disc storage device), a compact disc-ROM (CD-ROM),a digital versatile disc (DVD) or other types of optical storage device,and a magnetic cassette. Alternatively, the program may be stored in amemory configured by a combination of some or all of those describedabove. Further, each configuration memory may also be included inplural.

Further, the program may be stored in an attachable storage device thatmay be accessed through a communication network such as Internet,Intranet, a local area network (LAN), a wide LAN (WLAN), or a storagearea network (SAN), or a communication network configured by acombination thereof. Such a storage device may access an apparatusperforming the embodiment of the present disclosure through an externalport. Further, a separate storage device on a communication network mayaccess the apparatus performing the embodiment of the present disclosurethrough an external port.

In detailed embodiments of the present disclosure described above,components included in the present disclosure have been expressed in thesingular or plural according to the suggested detailed embodiment.However, the expression in the singular or plural is appropriatelyselected for the situation suggested for convenience of explanation, andthe present disclosure is not limited to a single component or aplurality of components. Even the components expressed in the plural maybe configured as a single component, or even the component expressed inthe singular may be configured as plural components.

While the present disclosure has been described in connection with thedetailed embodiments thereof, various modifications can be made withoutdeparting from the scope of the present disclosure. Therefore, the scopeof the present disclosure should not be construed as being limited tothe described embodiments but be defined by the appended claims as wellas equivalents thereto.

Second Embodiment

A second embodiment of present disclosure provides a method of using acorresponding resource if a terminal receives uplink resource allocationduring random access in a cell in which only a sounding reference signal(SRS) may be transmitted in uplink.

FIG. 2A illustrates a structure of an LTE system to which the presentdisclosure is applied.

Referring to FIG. 2A, the wireless communication system is configured ofa plurality of base stations 2 a-05, 2 a-10, 2 a-15, and 2 a-20, amobility management entity (MME) 2 a-25, and a serving-gateway (S-GW) 2a-30. A user equipment (hereinafter, UE or terminal) 2 a-35 accesses anexternal network through the base stations 2 a-05, 2 a-10, 2 a-15, and 2a-20 and the S-GW 2 a-30.

The base stations 2 a-05, 2 a-10, 2 a-15, and 2 a-20 as access nodes ofa cellular network provide radio access to terminals accessing thenetwork. That is, the base stations 2 a-05, 2 a-10, 2 a-15, and 2 a-20performs scheduling by collecting state information such as bufferconditions of the terminals, a power headroom state, a channel state,and the like to provide traffic to users, thereby supporting connectionbetween the terminals and a core network (CN).

The MME 2 a-25 which is an apparatus performing various controlfunctions in addition to a mobility management function for a terminalis connected to a plurality of base stations, and the S-GW 2 a-30 is anapparatus providing a data bearer.

Further, the MME 2 a-25 and the S-GW 2 a-30 may further performauthentication for a terminal accessing the network, bearer management,or the like, and process a packet arrived from the base stations 2 a-05,2 a-10, 2 a-15, and 2 a-20 or a packet to be transferred to the basestations 2 a-05, 2 a-10, 2 a-15, and 2 a-20.

FIG. 2B illustrates a wireless protocol structure of the LTE system towhich the present disclosure is applied.

Referring to FIG. 2B, a wireless protocol of the LTE system isconfigured of a packet data convergence protocol (PDCP) 2 b-05 and 2b-40, a radio link control (RLC) 2 b-10 and 2 b-35, and a medium accesscontrol (MAC) 2 b-15 and 2 b-30 in the terminal and an eNB,respectively. The PDCP 2 b-05 and 2 b-40 is responsible for an operationsuch as IP header compression/decompression, and the like, and the radiolink control (hereinafter, referred to as RLC) 2 b-10 and 2 b-35reconfigures a PDCP packet data unit (PDU) in an appropriate size.

The MAC 2 b-15 and 2 b-30 is connected to multiple RLC layer devicesconfigured in one terminal, and performs an operation of multiplexingRLC PDUs into an MAC PDU and demultiplexing RLC PDUs from an MAC PDU. Aphysical layer (PHY) 2 b-20 and 2 b-25 performs an operation ofchannel-coding and modulating higher layer data and transmitting thehigher layer data in a form of an OFDM symbol through a radio channel,or demodulating an OFDM symbol received through the radio channel andperforming channel decoding for transmission to a higher layer.

Further, the physical layer uses a hybrid automatic repeat request(HARQ) for additional error correction, and a reception end transmits 1bit information indicating acknowledgement/negative-acknowledgement forreception of a packet transmitted from a transmission end. This isreferred to as HARQ ACK/NACK information. Downlink HARQ ACK/NACKinformation for uplink transmission is transmitted through a physicalhybrid-ARQ indicator channel (PHICH) and uplink HARQ ACK/NACKinformation for downlink transmission may be transmitted through aphysical uplink control channel (PUCCH) or a physical uplink sharedchannel (PUSCH).

Although not illustrated in FIG. 2B, a radio resource control(hereinafter, referred to as RRC) layer exists as a higher layer of thePDCP layers of the terminal and the base station, respectively, and theRRC layer may receive and transmit a configuration control messagerelated to access and measurement for radio resource control.

Meanwhile, the PHY layer may be configured of one or a plurality offrequencies/carriers, and a technology of simultaneously setting andusing a plurality of frequencies is referred to as carrier aggregation(hereinafter, referred to as CA). In the CA technology, a primarycarrier and additional one or multiple subcarriers are used forcommunication between the terminal (or UE) and the base station (E-UTRANNodeB, eNB), rather than using only one carrier, thereby remarkablyincreasing a transmission amount as much as the number of subcarriers.Meanwhile, in the LTE, a cell in the base station using the primarycarrier is referred to as a primary cell (PCell), and a cell using thesubcarrier is referred to as a secondary cell (SCell).

FIG. 2C illustrates carrier aggregation in a terminal.

Referring to FIG. 2C, one base station generally transmits and receivesmultiple carriers over multiple frequency bands. For example, when thebase station 2 c-05 transmits a carrier 2 c-15 of which a centerfrequency is f1 and a carrier 2 c-10 of which a center frequency is f3,typically, one terminal transmits and receives data using one of the twocarriers. However, the terminal having the CA capability maysimultaneously transmit and receive the data from multiple carriers. Thebase station 2 c-05 may increase a transmission rate of the terminal 2c-30 having the CA capability by allocating more carriers depending on asituation.

When one downlink carrier and one uplink carrier that are transmittedfrom and received by one base station configure one cell, it may also beunderstood that the CA means that the terminal simultaneously transmitsand receives data through multiple cells. Through this, a maximumtransmission rate is increased in proportion to the number of aggregatedcarriers.

Hereinafter, in describing the present disclosure, data reception by theterminal through any downlink carrier or data transmission by theterminal through nay uplink carrier may have the same meaning as thatdata transmission and reception are performed using a control channeland a data channel provided in a cell corresponding to a centerfrequency and frequency band characterizing the carrier. Further,hereinafter, the embodiment of the present disclosure will be describedby assuming the LTE system for convenience of explanation, but thepresent disclosure may be applied to various wireless communicationsystems supporting the CA.

FIG. 2D illustrates a frame structure of a time division duplex (TDD)system having switch point periodicity of 5 ms of the LTE system. Thatis, it is a frame structure corresponding to configurations 0, 1, 2, or6 in Table at a lower portion of FIG. 2D. In a frame structurecorresponding to configurations 3, 4, or 5, only one special subframe tobe described below is at a position of #1 subframe in one frame, anddetailed description thereof will be omitted.

As illustrated in FIG. 2D, a length of one frame in the LTE is 10 ms,and this is again divided into 10 subframes having a length of 1 ms (#0,#1, #2, . . . , #9). Here, referring to Table at the lower portion ofFIG. 2D, #0, #2, #3, #4, #5, #7, #8, and #9 may be used as a downlinksubframe (indicated by “D” in Table) and an uplink subframe (indicatedby “U” in Table) according to TDD configuration. That is, in the case ofTDD configuration 0, subframes #0 and #5 are used as downlink subframes,and subframes #2, #3, #4, #7, #8, and #9 are used as uplink subframes,and in the case of TDD configuration 1, subframes #0, #4, #5, and #9 areused as downlink subframes, and subframes #2, #3, #7, and #8 are used asuplink subframes.

In FIG. 2D, subframes #1 and #6 are special subframes, which aresubframes in a transition period from downlink to uplink. That is, it isa slot divided into three fields of a downlink pilot time slot (DwPTS),a guard period (GP), and an uplink pilot time slot (UpPTS), in whichdownlink data transmission is possible in the DwPTS field, but uplinkdata transmission is not possible in the UpPTS field, and transmissionof a sounding reference signal (SRS) and the like is possible. The GP isan idle period in conversion between downlink and uplink.

FIG. 2E is a diagram illustrating message flow of a terminal and a basestation when applying the present disclosure. In the drawing, it isassumed that the terminal is already connected to the base station anddata transmission and reception are possible.

The terminal receives an instruction to additionally configure a TDDcell in which only the SRS may be transmitted in uplink as an SCell froma PCell (or an activated SCell) (2 e-11). The reason of adding the cellas described above is that since the terminal may not simultaneouslytransmit multiple uplink due to limitation in its function, practically,only downlink is received in the added cell, and when the terminaltransmits the SRS to the uplink subframe described above in FIG. 2D bytemporarily switching/moving to the added cell, the base stationreceives the transmitted SRS to check an uplink channel state to therebyguess a downlink channel state.

By doing so, the base station may save resources for channel statereport of the added cell. The configuration message may beRRCConnectionReconfiguration message of the RRC layer. Further, theconfiguration message may include one or more of SRS configurationinformation in the added cell, random access configuration informationin the added cell, and the like. The random access configurationinformation may include information indicating in which resource ofwhich uplink the terminal may perform random access, and the like.

The terminal receiving the configuration message transmits a messageindicating that the configuration message is properly received to thebase station (2 e-13). As the confirmation message, anRRCConnectionReconfigurationComplete message and the like may be used.

Thereafter, the terminal receives an activation message from the basestation to actually use the additionally configured cell (2 e-15).

Thereafter, the terminal receives instruction to transmit a preamble tothe added cell from the base station for obtaining a transmission timingto transmit the SRS to the added cell, or for other reasons (2 e-21).The message instructing the preamble transmission may include at leastone of a specific preamble identifier and information for limitingspecific resources among the configured random access resources.

The terminal transmits a random access preamble signal to the added cellaccording to the preamble transmission instruction (2 e-23). The basestation receiving the random access preamble transmits a random accessresponse message through the PCell (2 e-25). The response message mayinclude at least one of uplink transmission timing adjustmentinformation, uplink transmission resource information, and SRStransmission-related resource information.

According to the first embodiment of the present disclosure, theterminal receiving the response message does not transmit the data andthe SRS through the corresponding resource even though the uplinktransmission resource information is present.

According to the second embodiment of the present disclosure, the SRS istransmitted to the subframe to which the uplink transmission resource isallocated in the added cell.

According to a third embodiment of the present disclosure, if theresponse message includes the SRS transmission-related resourceinformation, the terminal transmits the SRS to the correspondingsubframe in the added cell according to the indicated information.

FIG. 2F illustrates an operation order of the terminal when applying thepresent disclosure. In the drawing, it is assumed that the terminal isalready connected to the base station and data transmission andreception are possible.

The terminal receives an instruction to additionally configure a TDDcell in which only the SRS may be transmitted in uplink as an SCell froma PCell (or an activated SCell) and transmits a confirmation messagetherefor (2 f-03). The reason of adding the cell as described above isthat since the terminal may not simultaneously transmit multiple uplinkdue to limitation in its function, practically, only downlink isreceived in the added cell, and when the terminal transmits the SRS tothe uplink subframe described above in FIG. 2D by temporarilyswitching/moving to the added cell, the base station receives thetransmitted SRS to check an uplink channel state to thereby guess adownlink channel state.

By doing so, the base station may save resources for channel statereport of the added cell. The configuration message may beRRCConnectionReconfiguration message of the RRC layer. Further, theconfiguration message may include one or more of SRS configurationinformation in the added cell, random access configuration informationin the added cell, and the like. The random access configurationinformation may include information indicating in which resource ofwhich uplink the terminal may perform random access, and the like.Further, as the confirmation message, anRRCConnectionReconfigurationComplete message and the like may be used.

Thereafter, the terminal receives an activation message from the basestation to actually use the additionally configured cell (2 f-05).Accordingly, the terminal may receive downlink data from thecorresponding SCell.

Thereafter, the terminal receives instruction to transmit a preamble tothe added cell from the base station for obtaining a transmission timingto transmit the SRS to the added cell, or for other reasons (2 f-07).The message instructing the preamble transmission may include at leastone of a specific preamble identifier and information for limitingspecific resources among the configured random access resources.

The terminal transmits a random access preamble signal to the added cellaccording to the preamble transmission instruction (2 f-09), andreceives a random access response message through the PCell of the basestation (2 f-11). The response message may include at least one ofuplink transmission timing adjustment information, uplink transmissionresource information, and SRS transmission-related resource information.

Thereafter, according to the first embodiment of the present disclosure,the terminal receiving the response message does not transmit the dataand the SRS through the corresponding resource even though the uplinktransmission resource information is present. Alternatively, accordingto the second embodiment of the present disclosure, the SRS istransmitted to the subframe to which the uplink transmission resource isallocated in the added cell. Alternatively, according to the thirdembodiment of the present disclosure, if the response message includesthe SRS transmission-related resource information, the terminaltransmits the SRS to the corresponding subframe in the added cellaccording to the indicated information (2 f-13).

FIG. 2G illustrates a block configuration of a terminal in a wirelesscommunication system according to an embodiment of the presentdisclosure.

Referring to FIG. 2G, the terminal includes a radio frequency (RF)processor 2 g-10, a baseband processor 2 g-20, a storage unit 2 g-30,and a controller 2 g-40.

The RF processor 2 g-10 performs a function for transmitting andreceiving a signal through a radio channel such as band conversion,amplification, and the like of a signal. That is, the RF processor 2g-10 up-converts a baseband signal provided from the baseband processor2 g-20 into an RF band signal and transmits the up-converted signalthrough an antenna, and down-converts the PF band signal receivedthrough the antenna into the baseband signal.

For example, the RF processor 2 g-10 may include a transmission filter,a reception filter, an amplifier, a mixer, an oscillator, a digital toanalog converter (DAC), an analog to digital converter (ADC), and thelike. In FIG. 2G, only one antenna is illustrated, but the terminal mayinclude a plurality of antennas. Further, the RF processor 2 g-10 mayinclude a plurality of RF chains. Further, the RF processor 2 g-10 mayperform beamforming. For the beamforming, the RF processor 2 g-10 mayadjust a phase and size of each of signals transmitted and receivedthrough the plurality of antennas or antenna elements.

The baseband processor 2 g-20 performs a function of conversion betweena baseband signal and a bit string according to a physical layerstandard of the system. For example, at the time of data transmission,the baseband processor 2 g-20 generates complex symbols by encoding andmodulating a transmission bit string. Further, at the time of datareception, the baseband processor 2 g-20 restores a reception bit stringby demodulating and decoding the baseband signal provided from the RFprocessor 2 g-10.

For example, according to an orthogonal frequency division multiplexing(OFDM) scheme, at the time of data transmission, the baseband processor2 g-20 generates complex symbols by encoding and modulating atransmission bit string, maps the complex symbols, and then configuresOFDM symbols through inverse fast Fourier transform (IFFT) operation andcyclic prefix (CP) insertion. Further, at the time of data reception,the baseband processor 2 g-20 divides the baseband signal provided fromthe RF processor 2 g-10 into OFDM symbol units, restores signals mappedto subcarriers through FFT operation, and then restores a reception bitstring through demodulation and decoding.

The baseband processor 2 g-20 and the RF processor 2 g-10 transmit andreceive a signal as described above. Accordingly, the baseband processor2 g-20 and the RF processor 2 g-10 may be referred to as a transmitter,a receiver, a transceiver, or a communication unit. Further, at leastone of the baseband processor 2 g-20 and the RF processor 2 g-10 mayinclude a plurality of communication modules to support a plurality ofdifferent radio access technologies.

Further, at least one of the baseband processor 2 g-20 and the RFprocessor 2 g-10 may include different communication modules to processsignals of different frequency bands. For example the different radioaccess technologies may include a wireless LAN (e.g., IEEE 802.11), acellular network (e.g., LTE), and the like. Further, the differentfrequency bands may include a super high frequency (SHF) band (e.g., 2.5GHz, 5 GHz), and a millimeter wave (mm wave) band (e.g., 60 GHz).

The storage unit eg-30 stores data such as a basic program for operationof the terminal, an application program, configuration information, andthe like. In particular, the storage unit 2 g-30 may store informationon a wireless LAN node performing wireless communication using awireless LAN access technology. Further, the storage unit 2 g-30provides the stored data in response to a request of the controller 2g-40.

The controller 2 g-40 controls overall operations of the terminal. Forexample, the controller 2 g-40 transmits and receives a signal throughthe baseband processor 2 g-20 and the RF processor 2 g-10. Further, thecontroller 2 g-40 records data in the storage unit 2 g-30 and reads thedata. To this end, the controller 2 g-40 may include at least oneprocessor. For example, the controller 2 g-40 may include acommunication processor (CP) performing a control for communication andan application processor (AP) controlling a higher layer such as anapplication program. According to an embodiment of the presentdisclosure, the controller 2 g-40 includes a multi-connection processor2 g-42 performing processing for operation in a multi-connection mode.For example, the controller 2 g-40 may control the terminal to performthe operation of the terminal illustrated in FIG. 2E.

When a TDD cell in which only the SRS may be transmitted in uplink isadded and a random access instruction is received from the base station,the controller 2 g-40 according to the embodiment of the presentdisclosure transmits a preamble according thereto, and uses resourcesincluded in a random access response message according to the embodimentdescribed above.

The methods according to the embodiments described in claims orspecification of the present disclosure may be implemented in a form ofhardware, software, or a combination of hardware and software.

In the case of implementation in the form of software, acomputer-readable storage medium that stores one or more programs(software module). The one or more programs stored in thecomputer-readable storage medium are configured for execution by one ormore processors in an electronic device. The one or more programsinclude instructions making the electronic device to execute the methodaccording to the embodiments described in claims or specification of thepresent disclosure.

The program (software module, software) may be stored in a random accessmemory, a non-volatile memory including a flash memory, a read onlymemory (ROM), an electrically erasable programmable read only memory(EEPROM), a magnetic disc storage device), a compact disc-ROM (CD-ROM),a digital versatile disc (DVD) or other types of optical storage device,and a magnetic cassette. Alternatively, the program may be stored in amemory configured by a combination of some or all of those describedabove. Further, each configuration memory may also be included inplural.

Further, the program may be stored in an attachable storage device thatmay be accessed through a communication network such as Internet,Intranet, a local area network (LAN), a wide LAN (WLAN), or a storagearea network (SAN), or a communication network configured by acombination thereof. Such a storage device may access an apparatusperforming the embodiment of the present disclosure through an externalport. Further, a separate storage device on a communication network mayaccess the apparatus performing the embodiment of the present disclosurethrough an external port.

In detailed embodiments of the present disclosure described above,components included in the present disclosure have been expressed in thesingular or plural according to the suggested detailed embodiment.However, the expression in the singular or plural is appropriatelyselected for the situation suggested for convenience of explanation, andthe present disclosure is not limited to a single component or aplurality of components. Even the components expressed in the plural maybe configured as a single component, or even the component expressed inthe singular may be configured as plural components.

Although the present disclosure has been described with an exemplaryembodiment, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

What is claimed is:
 1. A method performed by a terminal in a wirelesscommunication system, the method comprising: receiving, from a basestation, a message for configuring at least one secondary cell (SCell)including configuration information on an SCell of the at least oneSCell, wherein the configuration information on the SCell indicates thatuplink data transmission is not performed on the SCell; transmitting, tothe base station, a random access preamble for the SCell; receiving,from the base station, a random access response for the SCell includinginformation on a timing advance and an uplink grant; and applying theinformation on the timing advance for the SCell, based on the randomaccess response, wherein the uplink grant included in the random accessresponse for the SCell is ignored.
 2. The method of claim 1, wherein theconfiguration information further includes information on a soundingreference signal (SRS) configuration.
 3. The method of claim 2, furthercomprising: performing an SRS transmission on the SCell based on the SRSconfiguration.
 4. The method of claim 3, wherein an uplink datatransmission on another SCell of the at least one SCell is restrictedduring the SRS transmission.
 5. The method of claim 1, wherein themessage is a radio resource control (RRC) message.
 6. A method performedby a base station in a wireless communication system, the methodcomprising: transmitting, to a terminal, a message for configuring atleast one secondary cell (SCell) including configuration information onan SCell of the at least one SCell, the configuration informationincluding information for configuring the SCell not to transmit uplinkdata; receiving, from the terminal, a random access preamble for theSCell; transmitting, to the terminal, a random access response for theSCell including information on a timing advance and an uplink grant; andapplying the information on the timing advance for the SCell, based onthe random access response, wherein the uplink grant in the randomaccess response for the SCell is ignored by the terminal.
 7. The methodof claim 6, wherein the configuration information further includesinformation on a sounding reference signal (SRS) configuration.
 8. Themethod of claim 7, further comprising: receiving, from the terminal, anSRS on the SCell based on the SRS configuration.
 9. The method of claim8, wherein an uplink data transmission on another SCell of the at leastone SCell is restricted during a transmission of the SRS.
 10. The methodof claim 6, wherein the message is a radio resource control (RRC)message.
 11. A terminal in a wireless communication system, the terminalcomprising: a transceiver; and a controller configured to: control thetransceiver to receive, from a base station, a message for configuringat least one secondary cell (SCell) including configuration informationon an SCell of the at least one SCell, wherein the configurationinformation on the SCell indicates that uplink data transmission is notperformed on the SCell, control the transceiver to transmit, to the basestation, a random access preamble for the SCell, control the transceiverto receive, from the base station, a random access response for theSCell including information on a timing advance and an uplink grant, andapply the information on the timing advance for the SCell, based on therandom access response, wherein the uplink grant included in the randomaccess response for the SCell is ignored.
 12. The terminal of claim 11,wherein the configuration information further includes information on asounding reference signal (SRS) configuration.
 13. The terminal of claim12, wherein the controller is further configured to perform an SRStransmission on the SCell based on the SRS configuration.
 14. Theterminal of claim 13, wherein an uplink data transmission on anotherSCell of the at least one SCell is restricted during the SRStransmission.
 15. The terminal of claim 11, wherein the message is aradio resource control (RRC) message.
 16. A base station in a wirelesscommunication system, the base station comprising: a transceiver; and acontroller configured to: control the transceiver to transmit, to aterminal, a message for configuring at least one secondary cell (SCell)including configuration information on an SCell of the at least oneSCell, the configuration information including information forconfiguring the SCell not to transmit uplink data, control thetransceiver to receive, from the terminal, a random access preamble forthe SCell, control the transceiver to transmit, to the terminal, arandom access response for the SCell including information on a timingadvance and an uplink grant, and apply the information on the timingadvance for the SCell, based on the random access response, wherein theuplink grant in the random access response for the SCell is ignored bythe terminal.
 17. The base station of claim 16, wherein theconfiguration information further includes information on a soundingreference signal (SRS) configuration.
 18. The base station of claim 17,wherein the controller is further configured to control the transceiverto receive, from the terminal, an SRS on the SCell based on the SRSconfiguration.
 19. The base station of claim 18, wherein an uplink datatransmission on another SCell of the at least one SCell is restrictedduring a transmission of the SRS.
 20. The base station of claim 16,wherein the message is a radio resource control (RRC) message.